Upper for a slipper



FIG. 1 is a top plan view of an upper for a slipper according to my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a front elevational view thereof; and,

FIG. 4 is a left side elevational view thereof.

The bottom is plain and unornamented. The dashed lines are for environmental purposes only and form no part of this design. 

The ornamental design for an upper for a slipper, as shown and described. 